diff --git a/packages/frontend/vite.config.local-dev.ts b/packages/frontend/vite.config.local-dev.ts
index 5a6f511c66..6d9488797c 100644
--- a/packages/frontend/vite.config.local-dev.ts
+++ b/packages/frontend/vite.config.local-dev.ts
@@ -1,5 +1,7 @@
 import dns from 'dns';
+import { readFile } from 'node:fs/promises';
 import { defineConfig } from 'vite';
+import * as yaml from 'js-yaml';
 import locales from '../../locales/index.js';
 import { getConfig } from './vite.config.js';
 
@@ -7,6 +9,11 @@ dns.setDefaultResultOrder('ipv4first');
 
 const defaultConfig = getConfig();
 
+const { port } = yaml.load(await readFile('../../.config/default.yml', 'utf-8'));
+
+const httpUrl = `http://localhost:${port}/`;
+const websocketUrl = `ws://localhost:${port}/`;
+
 const devConfig = {
 	// 基本の設定は vite.config.js から引き継ぐ
 	...defaultConfig,
@@ -19,28 +26,28 @@ const devConfig = {
 		proxy: {
 			'/api': {
 				changeOrigin: true,
-				target: 'http://localhost:3000/',
+				target: httpUrl,
 			},
-			'/assets': 'http://localhost:3000/',
-			'/static-assets': 'http://localhost:3000/',
-			'/client-assets': 'http://localhost:3000/',
-			'/files': 'http://localhost:3000/',
-			'/twemoji': 'http://localhost:3000/',
-			'/fluent-emoji': 'http://localhost:3000/',
-			'/sw.js': 'http://localhost:3000/',
+			'/assets': httpUrl,
+			'/static-assets': httpUrl,
+			'/client-assets': httpUrl,
+			'/files': httpUrl,
+			'/twemoji': httpUrl,
+			'/fluent-emoji': httpUrl,
+			'/sw.js': httpUrl,
 			'/streaming': {
-				target: 'ws://localhost:3000/',
+				target: websocketUrl,
 				ws: true,
 			},
-			'/favicon.ico': 'http://localhost:3000/',
+			'/favicon.ico': httpUrl,
 			'/identicon': {
-				target: 'http://localhost:3000/',
+				target: httpUrl,
 				rewrite(path) {
 					return path.replace('@localhost:5173', '');
 				},
 			},
-			'/url': 'http://localhost:3000',
-			'/proxy': 'http://localhost:3000',
+			'/url': httpUrl,
+			'/proxy': httpUrl,
 		},
 	},
 	build: {